The answer is about 0.9km (can vary from 0.8 - 1 km) per hour.
What I did was find the slope using the points (0,0) and (9,8)
Apply the slope formula of slope = x2 -x1/ y2- y1
Plug in the numbers: 8 - 0 / 9 - 0
You’d then get 8/9, do the division and you’d get 0.89 (or 0.9 rounded to the tenth) km per hour